Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754112AbYKFBnY (ORCPT ); Wed, 5 Nov 2008 20:43:24 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753060AbYKFBnO (ORCPT ); Wed, 5 Nov 2008 20:43:14 -0500 Received: from mail.crca.org.au ([67.207.131.56]:57300 "EHLO crca.org.au" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752959AbYKFBnO (ORCPT ); Wed, 5 Nov 2008 20:43:14 -0500 X-Bogosity: Ham, spamicity=0.000000 Subject: Re: [linux-pm] [PATCH] hibernation should work ok with memory hotplug From: Nigel Cunningham To: KAMEZAWA Hiroyuki Cc: "Rafael J. Wysocki" , Dave Hansen , Yasunori Goto , Matt Tolentino , linux-pm@lists.osdl.org, Dave Hansen , linux-kernel@vger.kernel.org, linux-mm@kvack.org, pavel@suse.cz, Mel Gorman , Andy Whitcroft , Andrew Morton In-Reply-To: <20081106101751.14113f24.kamezawa.hiroyu@jp.fujitsu.com> References: <20081029105956.GA16347@atrey.karlin.mff.cuni.cz> <1225817945.12673.602.camel@nimitz> <20081105093837.e073c373.kamezawa.hiroyu@jp.fujitsu.com> <200811051208.26628.rjw@sisk.pl> <20081106091441.6517c072.kamezawa.hiroyu@jp.fujitsu.com> <20081106101751.14113f24.kamezawa.hiroyu@jp.fujitsu.com> Content-Type: text/plain Organization: Christian Reformed Churches of Australia Date: Thu, 06 Nov 2008 12:43:07 +1100 Message-Id: <1225935787.6216.12.camel@nigel-laptop> Mime-Version: 1.0 X-Mailer: Evolution 2.22.3.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1626 Lines: 48 Hi. On Thu, 2008-11-06 at 10:17 +0900, KAMEZAWA Hiroyuki wrote: > On Thu, 6 Nov 2008 09:14:41 +0900 > KAMEZAWA Hiroyuki wrote: > > > Ok, please consider "when memory hotplug happens." > > > > In general, it happens when > > 1. memory is inserted to slot. > > 2. the firmware notifes the system to enable already inserted memory. > > > > To trigger "1", you have to open cover of server/pc. Do you open pc while the system > > starts hibernation ? for usual people, no. > > > > To trigger "2", the user have special console to tell firmware "enable this memory". > > Such firmware console or users have to know "the system works well." And, more important, > > when the system is suspended, the firmware can't do hotplug because the kernel is sleeping. > > So, such firmware console or operator have to know the system status. > > > > Am I missing some ? Current linux can know PCI/USB hotplug while the system is suspended ? > > > *OFFTOPIC* > > I hear following answer from my friend. > > - hibernate the system > => plug USB memory > => wake up the system > => panic. > - hibernate the system > => unplug USB memory > => wake up the sytem > => panic. We currently check that the number of physical pages is the same when starting to load the image, so neither of these issues cause real problems. Regards, Nigel -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/